Heisenberg’s Uncertainty Principle

“Throughout the main body of his original 1927 paper, written in German, Heisenberg used the word, „Ungenauigkeit“ („indeterminacy“), to describe the basic theoretical principle. Only in the endnote did he switch to the word, „Unsicherheit“ („uncertainty“). When the English-language version of Heisenberg’s textbook, The Physical Principles of the Quantum Theory, was published in 1930, however, the translation „uncertainty“ was used, and it became the more commonly used term in the English language thereafter.”

Have you ever heard the story about Heisenberg driving on the autobahn? He’s speeding along, and he gets pulled over. The police officer says, “Do you have any idea how fast you were going?!” And Heisenberg says, “No. But I know exactly where I was!”

“The uncertainty principle says that we cannot measure the position (x) and the momentum (p) of a particle [at the same instant] with absolute precision. The more accurately we know one of these values, the less accurately we know the other.”